The present invention relates generally to downrigger cable reels, and more particularly to a rotary electrical coupling for a downrigger cable reel for transmission of electrical signals and power between a vessel and a downrigger cable.
A downrigger is a fishing implement used in conjunction with a fishing rod for deep water fishing on the Great Lakes and the oceans. A conventional downrigger has a line wound on a manually or electrically operated reel. A heavy weight is disposed at the end of the downrigger line which extends from the reel. A fishing line having a fish hook with bait or a lure affixed to it is detachably fastened to the downrigger line near the lower end thereof.
Both the downrigger line and the fishing line are lowered into the water to a desired depth. When a fish is hooked, the fishing line separates from the downrigger line as a consequence of the fish pulling on the fish hook. The fishing line pulls out of a line release device which is attached to the downrigger line. The fisherman may then play the fish without having the downrigger weight to contend with along with the fish.
As is well known, many species of fish prefer a limited range of cool water temperatures. The preferred temperature range can occur at great depth in the Great Lakes or oceans. Consequently, when fishing at such depths, the fisherman cannot see fish approach and strike the lure.
When fishing, it is desirable to be able to view the fish in the vicinity of the lure. Besides adding excitement to the fishing experience, viewing the fish provides a record in case the fish escapes. One way to view the fish at depth is to provide a camera device on a downrigger line that also serves as a cable suitable for transmitting real-time images of the lure and vicinity. One such system is described in commonly owned U.S. Pat. No. 6,036,499 to Ford.
In such an arrangement, the cable must be of a relatively small diameter to fit on a compact trolling reel and not to cause excess drag in the water. Further, the tensile strength must be relatively high since significant tension forces are placed on the line when payed out a significant distance with a heavy weight attached. The tension forces can be especially great if the cable becomes snagged.
It is also desirable to provide an electrical coupling scheme to provide power and receipt of image signals from the camera while the depth of the camera is changed by winding or unspooling the line from the reel.
The present invention provides a system which satisfies the above-discussed criteria while providing electrical continuity between the camera and the vessel.
The present invention provides a coupling system for a cable used to power and tow an electrical signal transmission device and convey the electrical signals therefrom.
The structure embodying the present invention is especially suitable for use with deep water fishing. The invention provides a plurality of electrically conductive paths between an electronic device such as an underwater camera and the boat. The connectivity of the paths is maintained while the depth of the camera is changed.
The rotational coupling system of the present invention is suitable for use with a downrigger cable, and includes a cable reel assembly having a main body and a cable reel rotatably mounted to the main body for winding the downrigger cable. A rotary electrical coupling is operably connected to the main body and to the cable reel for transmission of an electrical signal therebetween as the downrigger cable is wound onto the cable reel. The rotary electrical coupling comprises a rolling electrical contact bearing which can include contact elements such as balls, rollers, needles and the like. The rotary electrical coupling can be utilized in conjunction with an underwater camera, underwater temperature sensors, sonar, and the like devices.